Build aggregate routes

In many applications it is necessary for many or all of the nodes in the network to transmit data to a central aggregator node. In a new DigiMesh network the overhead of these nodes discovering routes to the aggregator node can be extensive and taxing on the network. To eliminate this overhead, use the AG command to automatically build routes to an aggregate node in a DigiMesh network.

Send a unicast

To send a unicast, devices configured for Transparent mode (AP = 0) must set their DH/DL registers to the MAC address of the node which they need to transmit to. In networks of Transparent mode devices which transmit to an aggregator node, it is necessary to set every device's DH/DL registers to the MAC address of the aggregator node. Use the AG command to set the DH/DL registers of all the nodes in a DigiMesh network to that of the aggregator node.

Use the AG command

Upon deploying a DigiMesh network, send the AG command on the desired aggregator node to cause all nodes in the network to build routes to the aggregator node. You can use the command to automatically update the DH/DL registers to match the MAC address of the aggregator node.

The AG command requires a 64-bit parameter. The parameter indicates the current value of the DH/DL registers on a device which should be replaced by the 64-bit address of the node sending the AG broadcast. If it is not desirable to update the DH/DL of the device receiving the AG broadcast, you can use the invalid address of 0xFFFE. API enabled devices output an Aggregate Addressing Update - 0x8E if they update their DH/DL address.

All devices that receive an AG broadcast update their routing table information to build a route to the sending device, regardless of whether or not their DH/DL address is updated. This routing information will be used for future transmissions of DigiMesh unicasts.

Example 1: To update the DH/DL registers of all modules in the network to be equal to the MAC address of an aggregator node with a MAC address of 0x0013a2004052c507 after network deployment the following technique could be employed:

  1. Deploy all devices in the network with the default DH/DL of 0xFFFF.
  2. Send an ATAGFFFF command on the aggregator node.

Following the preceding sequence would result in all of the nodes in the network which received the AG broadcast to have a DH of 0x0013a200 and a DL of 0x4052c507. These nodes would have automatically built a route to the aggregator.

Example 2: To cause all nodes in the network to build routes to an aggregator node with a MAC address of 0x0013a2004052c507 without affecting the DH/DL of any nodes in the network, send the AGFFFE command on the aggregator node. This sends an AG broadcast to all nodes in the network.

All of the nodes will update their internal routing table information to contain a route to the aggregator node. None of the nodes update their DH/DL registers, because none of the registers are set to an address of 0xFFFE.